Thursday, November 19, 2009

Magpies Part 2: Alien Intelligence

When I learn and think about other creatures, the thing that interests me most is their perspective. What must it be like to see the world as a pentachromatic Pigeon sees it? Or as a Dragonfly with ~360 degree vision and a 200Hz flicker rate? Or what would it be like to “see” the world through sound, like a bat or a dolphin? Or even weirder, and harder (at least for me) to envision: what must it be like to “see” the world through smells, like your dog? Think about it. You’re probably around dogs at least once a day. But your whole life, you’ll never really understand what it’s like to see the world how a dog sees it. There’s probably no animal more familiar to most of us than a dog, and yet when it really comes down to it, their perspective is forever alien to us; we can understand and get to know and maybe even love them, but we can’t ever get inside their heads.

Tangent: In fairness, dogs could say the same of us. No matter how familiar they become with us, so much of what we do must be forever cloaked in mystery. Certainly they can never understand what most of us actually “do” all day (work), but on a more mundane level, I often wonder if they truly “get” cars. Oh sure, they understand that we all get in the car and go someplace. But do they understand that the driver’s actions control where the car goes?

Or for that matter, does it even occur to them that the driver decides where the car will take them? Or do they assume (quite logically, actually) that our relationship to the car is more like theirs: you get in, close the door and it takes you someplace- someplace you don’t decide. Then you get out and do stuff for a while before getting back in the car which then takes you home.

In my darkest moments, I wonder if this fundamental alien-ness really applies to all “selves”, whether “self” can ever, really truly communicate with “other.” Certainly politics, religion and workplace meetings are all routinely characterized by people talking past each other, and regularly failing to get inside other people’s heads and see the world from their perspective. When you really get down to it, can any of us ever really communicate with our colleagues, our friends, or even our spouse? Or are we simply engaging in a never-ending verbal and non-verbal dance of positioning, assessing and bilaterally manipulating each other, each of us ultimately alone, inside an impenetrable shell of “self”?

OK, lighten up. I don’t really think that*. And I’ll tell you why. Because the longer I live and the more I learn about people, the more I see that most people are more or less the same, with similar hopes and dream and worries. And as I’ve gotten to know about animals, I’ve come to gain a similar perspective about them. Because even though we perceive the world radically differently than horses or coyotes or chimpanzees or porcupines do, we all think. And we all think with brains that, while different in size and form, all share a basic, fundamental structure, with parts and components that do more or less the same types of things in all of us. And so while we may never “see” the world as dogs see it, I’m convinced that we know what it is like to think, to experience, many things- hope, surprise, sadness, fear, affection, satisfaction, and maybe even wonder- much as they do. And when I think about that, the world doesn’t seem quite so lonely.

*Not most of the time anyway. Usually only after elections in Utah.

But then there’s birds. The most interesting thing about Magpies isn’t their nests or tails or the color of their bills- it’s their brains.

Among birds, corvids are regarded as some of the most intelligent*. Nearly all of us have heard some smart crow or raven story- how they cleverly stole food or outwitted a dog or some such. Rather than just recite a whole list, I’ll tell you my absolute favorite:

*The other contenders, which may be even more intelligent, are large parrots and macaws.

2 New Caledonian Crows, Corvus moneduloides (pic right),were in a cage*. In the cage was a little bucket with a handle down below where the crows couldn’t reach. Also placed in the cage were 2 wires, one straight, and the other bent into a hook. The idea of course was to see whether the crows would pick up the hooked wire and use it to retrieve the bucket. This in and of itself wouldn’t be all that shocking. Several corvids have been known to use other objects as tools. Caged Blue Jays for example have been observed using folded strips of newspaper to obtain food from cracks/crevices where their bills or talons couldn’t fit.

*OK, this sounds like the set-up for a geeky ornithological joke, doesn’t it?

But what actually happened was this: One of the 2 crows- the male*- snatched the hooked wire away. Then the female bent the straight wire into a hook and used it to retrieve the little bucket. Wow.

*Of course it was the male, right?

New Caledonian Crows are the champion tool-makers of the avian world; in the wild they’ve been observed fashioning twigs and leaves into tools to extract grubs from holes and crevices. Several corvids use tools, but C.moneduloides is the only one known to make them. And perhaps even cooler, they teach other New Caledonian Crows how to fashion the same tools. The only other animals known to use tools with the same proficiency as corvids are primates.

Tangent: New Caledonian Crow. Which is endemic to- that’s right- New Caledonia. Are you kidding me? That place again? How many times do we keep winding up back there in this blog? At least 10, that’s how many! Rare trees, parasitic conifers, ratites and now genius crows, all on the fragment of an ancient supercontinent- seriously- How. Cool. Is. That. Place?

I’m not superstitious, but this project keeps leading me back there again and again and again. OK that’s it- I’m saying it right now, right here: Some way, somehow, in the next 5 years, I am getting my ass to New Caledonia. Enough is enough.

Closer to home many of our local corvids display impressive mental faculties as well. A favorite of mine is Clark’s Nutcracker, Nucifraga columbiana, which- incredibly- keeps track of the locations of up to 2,500 seed caches made over the year over a range of ~150 square miles. If I leave my keys in 1 room, my wallet in another, and my phone in a 3rd, it is guaranteed that I will lose one of them within 15 minutes.*

*And that, once I break down and ask for help, Awesome Wife will locate the item in question in just 30 seconds.

Corvids also score well in tests of object permanence, the understanding that objects continue to exist when out of sight, something which takes a human a year or so to figure out*. Object permanence is measured and rated through a series of tests, in 6 stages, 6th being the highest. Eurasian Jays (Garrulus glandarius) (pic left) have achieved stage 6, a level matched only by primates. Magpies (specifically the Eurasian Black-billed Magpie, Pica pica) have clearly achieved stage 5, and possibly stage 6. Interestingly, Magpies don’t become fully independent of their parents until reaching stage 4 or 5.

*This has been the accepted conventional wisdom since the 1950’s. More recent research has begun to question this however, suggesting that human infants display a sense of object permanence when just a few months old.

But even more interesting is the social intelligence of many corvids. Ravens, crows and magpies in particular display many advanced forms of social intelligence, including the formation of coalitions and alliances (like chimpanzees and dolphins), social learning and tactical deception. For example Ravens will typically delay caching food items until out of sight of other ravens, and will even make false caches in view of their fellows in hopes of throwing them off.

Getting back to Clark’s Nutcracker for a moment, another corvid that regularly collects and caches pine nuts is of course the Piñon Jay, Gymnorhinus cyanocephalus (pic left). While Clark’s Nutcracker is pretty much of a loner, Piñon Jays are highly social, with apparently higher social intelligence. When tested on ability to perform various tasks- opening food containers, discriminating between different colored containers- Piñon Jays learned much faster by observing other Piñon Jays, whereas Clark’s Nutcrackers benefitted little by watching other Clark’s nutcrackers perform. Similarly, Piñon Jays and Clark’s Nutcrackers both display impressive ability in re-locating their own nut caches, but Piñon Jays show much greater ability in locating the caches of other Piñon Jays. Clark’s Nutcracker is smart, but a Piñon Jay shows higher social intelligence.

Tangent: Know what Clark’s Nutcracker reminds me of? Orangutans. An advanced primate, very intelligent, with a huge neocortex- which should mean a high Dunbar number- but largely solitary. Orangutans are suspected to have evolved from more social primates, but subsequently taken up a more solitary lifestyle. Similarly Clark’s Nutcracker is thought to share a common ancestry with more social corvids, and perhaps later followed a more solitary path. There’s something both weird and strangely admirable in such a possible story- if true- for either primate or corvid: a creature that turned away from socialization, that applied its impressive mental faculties away from its fellows and toward the physical world around it.

Even further off-topic, I can’t help but notice another possible parallel: humans with Aspberger’s syndrome. Is there some common thread? Something switched off, or even cast aside? Could Aspberger’s “suffererers” be not disabled, but just going following a different mental path?

Unsurprisingly, these birds, and corvids in general, have big brains. As a rule birds have a smaller brain weight-to-body weight ratio than mammals, though a much larger ratio than reptiles, who in turn have a much larger ratio than fish. But corvids have a ratio more like that of mammals, or even specifically primates*.

*But again, large parrots and macaws may be even more impressive, with a ratio almost 2/3 as big again. It’s interesting that while corvids have thrived world-wide, parrots and macaws have remained restricted to a far narrower tropical (and neotropical) range which is now under pressure from human expansion and development. Kind of like… chimpanzees.

So great. Magpies are smart. They have big brains. So what?

One of the most interesting things about birds is that they’ve solved so many of the same problems mammals have solved- color & foveal vision, thermoregulation and sex-determination are examples we’ve looked at in this blog- in fundamentally different ways*. The evolution of intelligence is another.

*The evolution of the ear is yet another example, which I had hoped to blog about before doing this post, but I felt I’d put this one off long enough.

I’ve mentioned in passing in this blog that I used to be into science fiction when I was younger, but gradually lost interest, probably in part because I “grew up”, but also in part I suspect because I found so much of the genre formulaic and unimaginative. In particular, I was almost always disappointed by depictions of aliens, who were invariably creatures who thought more or less like us, except they were generally less fun. Vulcans, Romulans, Klingons, War-Of-the Worlds Martians, Cylons, the Borg, the Visitors- they were all so dull, because they really weren’t different from us. And yet that’s what makes- or should make- the very idea of alien intelligence so darn interesting- that it would be different from us.

Tangent: The aliens of Star Trek- the original series- were particularly disappointing. The very first alien race we were introduced to were… Humorless White Guys with Pointy Ears. Really? That’s “alien?” Hell, at work I can work over to IT and see that anytime. And the Klingons*? Dark-Complected Sweaty Angry Guys with Facial Hair. You know, that’s pretty much me half-way through a bike race. And then the Romulans- still more Humorless White Guys with Pointy Ears- oh come on! Give us something else- a long nose? A third eye? Anything! I swear, you see more diversity at a Utah Republican Party convention…

*Again, in the original series, before Next Generation tarted them up with skull-ridges and such…

So here’s the thing about corvids: they’re the closest thing to intelligent aliens any of us will likely ever meet- far more alien than any of the fictional aliens listed above. Because corvids are living thinking creatures with exceptional memories, powerful tool-using capabilities and advanced social intelligence- just like primates- but with a radically-differently structured brain that evolved along a completely independent evolutionary path.

Side Note: Corvids (and many other birds), BTW, like primates, engage in social grooming. With birds it’s called allopreening. We humans no longer engage in social grooming of course*; the pop-anthropology explanation is that we now accomplish the same social bonding through chit-chat.

All the mammals I listed above share a common brain architecture which I touched upon in the Dunbar Number post last Spring. The top hunk of the mammalian brain is the cortex, which handles things like memory, awareness and perception. The outermost layer of the cortex is the neocortex, which is big and wrinkly in things like people, apes and dolphins, and which is associated with both higher-order intelligence in general and specifically social intelligence. I won’t repeat the whole story here; you can go check out the that post if you’re interested in the details. But the thing with birds- even smart birds like corvids, who use tools and have obvious high social intelligence- is that they have no neocortex.

Birds and mammals last shared an ancestor probably around 280 million years ago. That common ancestor almost certainly had a brain that would be characterized as “reptilian” today. You can think of a reptile’s brains as a stripped-down version of a mammal’s; it lacks a neocortex or a limbic system (hippocampus, amygdala), which is thought to be responsible for emotions beyond fear and anger. Over the ensuing 280 million years, mammals evolved these additional components, leading to the brains- and minds- we experience today.

Bird brains (diagram right, not mine) also evolved, but along a completely independent path which is reflected in their brain-structure. In birds the forebrain has developed and expanded, creating a structure called the nidopallium*, which appears to perform the same kinds of higher-order cognitive and social intelligence functions handled by the neocortex in mammals. Both neocortex and nidopallium developed out of an area called the pallium in the reptilian brains, but are constructed very differently. While the neocortex is organized in a layered structure, the avian forebrain appears more “nucleated” without any real layering**. It’s suspected- though yet unproven- that the nidopallium may contain a higher density of neurons than the mammalian neocortex, enabling greater brain activity in a more limited space.

*It used to be called the hyperstriatum, but was renamed within the last decade. You’ll still find the old name in many sources.

**An exception is a small area called the Wulst region, consisting of 3 or 4 layers, which seems to be involved in visual processing.

So the structure of bird brains is very different. Here’s one more Magpie story: In 2008, German researchers produced evidence that Magpies recognize themselves in a mirror, as shown by “mirror-induced self-directed behavior”, in this case using a mirror to reach and manipulate a mark on their bodies not visible without the mirror.

The sample size was small (5) and the success rate modest (3 out of 5) but this is more significant than you might think. Clear mirror self-recognition has been observed in chimpanzees and orangutans, but only maybe/possibly in gorillas. And even in chimpanzees, the self-recognition rate was only 75% in young adults, and lower in older and younger animals. In apes, such mirror-induced behavior has been taken as evidence of self-recognition, or a sense of self. Magpies, with their completely separate-from-us evolutionary history and their totally alien brains, appear to have independently evolved a sense of self.

That’s right- those annoying squawking birds, those “flying rats”*, with their fundamentally alien minds, are apparently self-aware, just like us. Now that’s a cool bird. (Pic right = Yellow-Billed Magpie in Yolo County, CA, taken by reader Alexis. It’s the best shot in this series- make sure to click on it. Thanks Alexis!)

*Coworker Sid’s description.

I’m not sure why, but I like that self-awareness, even intelligence, can evolve in different ways. It somehow makes the makes the world seem just a little less lonely, and hints at all sorts of crazy possibles across the big, wide universe. I’ll wrap up the post here; there’s something I want to go chat about with Awesome Wife.

16 comments:

When I was in high school my neighbor had a pet crow. It was fascinating to watch. You could absolutely tell from it's behavior that it was more intelligent than most animals.

It loved to torment their kitten. It would watch the kitten from up in a tree and when the kitten turned it's back and the situation was just right, it would swoop down and buzz the cat. Often it would also grasp the kitten's tail in it's beak and flip the cat - by the time the kitten regained it's senses the bird was gone and the kitten had no idea what just happened.

One of your better posts, particularly in its thought-provoking nature. And I don't give that praise lightly. Nice work.

One of the more fascinating anecdotes I've heard recently is about how we humans perceive the world around us visually. If we imagine the band of visual light in the context of the full electromagnetic spectrum as the one inch slit in a burqa (the analogy used not being accidental in this case), then the black fabric on either end of the one inch slit that we can "see" would stretch for miles in either direction. If we factor in how bats "see" with their ears and dogs with their noses, and add those senses to the range of the electromagnetic spectrum invisible to us, it's remarkable how much we're missing out on.

The beauty of science and mathematics is that it allows us to attempt to understand so much of what we wouldn't otherwise perceive. Sensible people may disagree as to whether this points to or away from the existence of a god. The only insensible conclusion is to deny the evidence before us.

OK, I maybe didn't do a good job describing the analogy above. To clarify, the electromagnetic spectrum is the burqa. The one inch slit is the portion of that spectrum that is visible light. The miles of black cloth on either end are all the other wavelengths in the electromagnetic spectrum from radio waves to gamma rays that we can't see. In other words, we can't see a whole lot more than we can, but it's no less real. Bees, for instance, see a different portion than we do, missing red but gaining ultraviolet in its place. Remarkable stuff.

KKris- That may be an even better corvid story than any I’ve read yet. And on a serious note, what’s cool about it is it shows mischief. Reptiles don’t show mischief (that I know of.) So what selection pressure drove both mammals and birds to evolve mischief independently? Anyway, it makes you think…

SBJ- No, you explained it well- I totally got it. It is sobering what a little slice of the world we actually sense. If we were exposed to the colors, sounds, smells that birds, bugs, bats and dogs “see”, I think our little minds would be overwhelmed.

Okay, I'll weigh in with a great magpie story I heard from a friend (wish it was first-hand), as best I remember it. She saw a dead magpie in her yard and swears she witnessed a magpie funeral.

Another magpie came and observed the dead magpie. Then it called and called, and other magpies came. They all stood in a big circle, and one would go into the middle of the circle and squawk a bunch and then retreat, then another would come up and do the same. When they were done they all took off.

Anyway, great post. I heartily concur (with both conclusions) about inter-human communication. And I've always wondered how we know whether what we call "red" (for example) is the "same color" that other people call "red."

Recent studies have also shown that crows can recognize individual human faces. They can also remember if that person has mistreated or threatened them in some way in the past and will warn other crows.

Have you read the Bernd Heinrich book about ravens? I read it a long time ago but it was fascinating. He's a now-retired Dartmouth biologist who's spent huge amounts of time observing ravens, both some that lived in captivity and in the field.

When I googled it, I saw that he's now written 2 books on ravens. I'm not sure which one I read... but he's an engaging writer who makes fascinating observations.

Steve- Thanks for the link, very interesting article. I came across a different account of the same effect when researching this post (but now can’t recall the source.) The context was researchers climbing trees to check on crow nests. When the specific researchers who had manhandled (measured) the eggs on the previous ascent returned they were squawked at/mobbed.

Your comment also reminds me of a nugget I meant to work into the post but then forgot: they think one of the ways magpies recognize each other is by the specific pattern of white-on-black feathers. Apparently the patterns run in “families.”

KB- I’m a huge Bernd Heinrich fan- I’ve read Winter World, A Year in The Maine Woods, The Trees In My Forest (he’s found living, healthy, blight-free, mature American Chestnuts on his property!) Why We Run, The Snoring Bird, and The Mind of the Raven (which includes an eyewitness account of a raven raiding a magpie nest.) His first raven book was Ravens In Winter, which I haven’t yet read. Next up is his latest, Summer World- I can’t wait! (I also keep meaning to read Bumblebee Economics…)

I'm embarrassed to admit that I know the "official" Star Trek explanation for why all of the aliens are so humanoid (besides the obvious budget explanation)... The Next Generation episode entitled "The Chase" revealed that all humanoids had a common ancestor who spread their DNA around the galaxy long ago... there, now I can go back to building my light saber replica and trying to talk like Jar-Jar...

Sally, I too have considered your color perception question. Philosophically and with no research, the conclusion I come to is this: while it's possible that we may not perceive the same colors exactly the same way, it's not likely that we could flip-flop, i.e. your red is my blue and my blue is your red. I don't think it would be possible to reverse the colors that way because they are perceived based on the wavelength of the light and those wavelengths aren't going to change from person to person.

Possible, however, is a color shift. For instance, your red is my orange, your green is my blue, etc. My red would therefore be some color you've never perceived, while your violet would be some color I've never perceived, even though we're seeing essentially the same range of wavelengths of light.

Most likely, however, is that we perceive color more or less the same given similar structures in the eyes and brain. The exception obviously being tetrachromatic women.

Of course the preceding is all just my own thought experiment on the topic, and I could easily be dead wrong. I know that the range of sound frequency humans hear varies slightly from individual to individual. It makes sense then that the range of frequencies in the visible spectrum varies somewhat from individual to individual, I just have no idea by how much.

I just got done reading "The Art of Racing in the Rain", which is actually told from a dog's persepctive. (I mean, obviously it's fiction, but it's neat anyway). It also has a very negative reference to crows, with a funny story. Great post - and I received my WatcherSticker... where to put it...

I recently only just realised that what I really want to do is biology (I'm switching subjects in Uni next year- don't tell my mum!) and your posts are fascinating!

Love all the stuff about insect eyes and magpie brains (that story about the female bending the wire is great) and it's definitely renewed my determination in pursuing something biology-based. (=

(Embarassingly, it was the movie Avatar that first got me thinking more deeply about this kind of thing, and what I wanted to do. I've written an article about it on my blog, if you haven't seen it already I'm sure you'd find it fascinating)

Penhaligon- Thanks for the kind words, and glad you're enjoying the blog. Your profile is hidden, so I can't see your blog or the post you reference; leave a pointer and I'll check it out.

If your heart's in biology, then follow it. I always knew I chose the wrong career (engineering then sales), but it took me 40 years to realize what path I should have followed. Sounds like you figured it out a lot quicker. Good for you!